2023 Volume 62 Issue 1 Pages 210-215
In this study, Sn–Graphene (Ag) composite plating films were fabricated on copper alloy substrates using a hybrid plating method, and the effects of addition and concentration of Ag+ in plating bath on various properties were investigated. It is found that the defect density of graphene in composite films decreased with increasing Ag+ concentration. The as–plated Sn–Graphene (Ag) composite film exhibited excellent electrical contact resistance of 0.49 mΩ, which is 49% lower than those of pure Sn and 20% lower than that of Sn–Graphene composite plating films, and even lower than that of pure Ag plating film (0.61 mΩ). In particular, it was confirmed that the Sn–Graphene (Ag) composite films showed stable resistance in the resistance–load change profiles and even after being heated at 200°C for 150 h. The contact resistance of the pure Sn plating increased more than doubly after the heating test, whereas the Sn–Graphene (Ag) composite films increased only about 30% and maintained the same level of conductivity as the pure Ag plating film, indicating the effective enhancement of conductivity and heat resistance by the inclusion of Ag–doped graphene in Sn matrix plating films even under a long–term high temperature environment.
